How can I define a type that "implements" an interface?

Question

Classes can implement interfaces:

interface ClockInterface {
    currentTime: Date;
}

class Clock implements ClockInterface {
    currentTime: Date;
    constructor(h: number, m: number) { }
}

How can I define a type that "implements" an interface? I don't understand why the following does not work, as it looks completely reasonable to me:

type DigitalClock implements ClockInterface = {
    currentTime: Date;
    somethingDigital: any;
}

That type is simply the interface. You can extend interfaces from other interfaces. — jo_va, Feb 26 '19 at 11:01
Possible duplicate of [What is the "type" reserved word in TypeScript?](https://stackoverflow.com/questions/31364693/what-is-the-type-reserved-word-in-typescript) — Igor, Feb 26 '19 at 11:15

score 2 · Answer 1 · answered Feb 26 '19 at 11:31

2

Just use

type DigitalClock = ClockInterface & {
    somethingDigital: any;
}

answered Feb 26 '19 at 11:31

Nguyen Phong Thien

3,237
1
15
36

How can I define a type that "implements" an interface?

1 Answers1